Week 10: Done with plastic wheels

Part A: Question Guide for Huang Ayi

1. How do you like the idea of making a trailer for the water bucket?

2. Do you think we achieve the functionality of it?

3. Can you describe what excites you most about the idea and why?

4. Can you guess what material we used for the wheels?

5. Do you like the material we choose -- a blend of wood and HDPE plastics?

6. How can we improve the exterior of it, such as shape and color?

7. In which way do you usually hold the handle or how can we fit the handle on to help you hold it in a more convenient way?

8. Do you think we need to increase the smoothness of the wheel when it’s turning in different directions?

9. Do you think the size of the trailer is too big or too small?

10. Will the trailer take up too much space for you to rest in your room?

11. Will you show this trailer to Ayi’s on other floors?

Part B: Recording for making the prototype

For this week, we began to collect more plastic bottle caps from the garbage station in NYUSH and a bubble tea shop beside Kevin's apartment since we need about 700-800 bottle caps in total to make those wheels, ring and the handle.

Prototyping Process Considering about the safety elements and efficiency, Kevin and I decide to work in pairs to make the final product instead of dividing tasks. Last time, we've tried to use CNC machine to cut HDPE bricks into the shape of wheel and locks. And we success! In this case, we just copy the Adobe Illustrator file and cut another two bricks by using the exactly same method. Since the size of the HDPE brick and also the thickness is very identical, we do not need to re-program the application but using the same controlling file to cut the rest of the bricks.

After that, we decided to polish them manually first by using number 180, 400, 600 and 800 sand papers. The wheels get much smoother! At the same time, Kevin used the drill mill to drill center holes to put the axis in. We observed that when the wheels spinning, there's large fiction between wheel and new materials. Therefore, we thought about an idea of sticking mental rings around wholes on each component to reduce the fiction. We continuously repeating this process for about four hours and finally combined all wheels and brackets to support the wheel!

Then, we drilled 4mm wholes on the wood board and 3.5 mm wholes on the bracket. We used two 4mm x 50mm screws to combine the wood and one of the bracket. After finishing installing the wheels, we used another two screws to connect the other brackets to the wood board. We were doing this because the axis wouldn't slide out while using the trailer.

Finally, we screwed all four wheels onto the wood board by using the hand drill. We adjusted the location and changed the length of the screw several times to ensure the wheels can spin smoothly. In addition, since the trailer needs to afford the weight of bucket filled with water, we tested the strength of trailer supports. The result showed that Andy and I were all able to stand on the trailer when the trailer can still be pulled easily. We also tested it on both the slop and flat surface, it functioned well and can turn directions easily!